Search

This paper concentrates on establishing a connectivity graph between building entities to model hazard flow and the interaction between pedestrians and hazards. Although three different ways are explored, the Uniform raycast-based approach resulted in being the most robust. We establish a link between hazards, indoor spaces and pedestrians through voxels, where navigable voxels are first derived, and further classified as IfcSpace and IfcDoor. In the end, only voxels with unique properties are kept, being < 1% of the total number of a building. Once the connectivity graph and voxels are identified the interaction between pedestrians and hazards is presented as straightforward. [ABSTRACT FROM AUTHOR]

The article presents a methodology for supervised regionalization of data on a spatial domain. Defining a spatial process at multiple scales leads to the famous ecological fallacy problem. Here, we use the ecological fallacy as the basis for a minimization criterion to obtain the intended regions. The Karhunen-Loève Expansion of the spatial process maintains the relationship between the realizations from multiple resolutions. Specifically, we use the Karhunen-Loève Expansion to define the regionalization error so that the ecological fallacy is minimized. The contiguous regionalization is done using the minimum spanning tree formed from the spatial locations and the data. Then, regionalization becomes similar to pruning edges from the minimum spanning tree. The methodology is demonstrated using simulated and real data examples. [ABSTRACT FROM AUTHOR]

Multi-view Stereo (MVS) meshes suffer from occlusions or missing data, making most surface reconstruction methods invalid. Due to data imperfections, existing methods, just like PolyFit, have made a trade-off between reconstruction accuracy and time consumption. We propose a novel approach that automatically reconstructs a building surface model from raw triangular mesh with data incompleteness. Unlike existing methods that extract high-quality primitives, our method focuses on assemblies of primitives to control the level of geometric detail in the reconstructed models. We design a topological relationship of the primitives to form a plane connection graph. To be precise, we first combine the scalability of shapes with plane primitives. Then strong and soft connections between primitives are constructed by calculating the confidence of the plane intersection in space. Furthermore, the topological relations of all primitives are encoded into an undirected graph. Finally, a watertight and manifold model is extracted from the faces of a candidate set by energy minimization. Experiments on the Helsinki 3D dataset demonstrate the superiority of our method in time consumption and reconstruction error, as measured by Hausdorff distance. Our method outperforms other primitive-based algorithms in handling non-planar structures. Even when dealing with imperfect data, a watertight model is still obtained. [Display omitted] • Due to the occlusion caused by various reasons such as trees, we designed a lightweight data structure and general strategy to rectify the building data defects. A confidence strategy combining graph structure is proposed, which reduces the time consumption compared with the state-of-art methods and captures more accurate geometric details within the reconstruction pipeline to generate building models with higher levels of detail. [ABSTRACT FROM AUTHOR]

In this work we continue the investigation of different approaches to conception and modelling of composite materials. The global method we focus on, is called ‘stochastic homogenization’. In this approach, the classical deterministic homogenization techniques and procedures are used to compute the macroscopic parameters of a composite starting from its microscopic properties. The stochastic part is due to averaging over some series of samples, and the fact that these samples fit into the concept of RVE (Representative Volume Element) in order to reduce the variance effect. In this article, we present a novel method for computation of effective electric properties of composites – it is based on the analysis of the connectivity graph (and the respective adjacency matrix) for each sample of a composite material. We describe how this matrix is constructed in order to take into account complex microscopic geometry. We also explain what we mean by homogenization procedure for electrical conductivity, and how the constructed matrix is related to the problem. The developed method is applied to a test study of the influence of micromorphology of composites materials on their conductivity. [ABSTRACT FROM AUTHOR]

Although, in most animals, brain connectivity varies between individuals, behaviour is often similar across a species. What fundamental structural properties are shared across individual networks that define this behaviour? We describe a probabilistic model of connectivity in the hatchling Xenopus tadpole spinal cord which, when combined with a spiking model, reliably produces rhythmic activity corresponding to swimming. The probabilistic model allows calculation of structural characteristics that reflect common network properties, independent of individual network realisations. We use the structural characteristics to study examples of neuronal dynamics, in the complete network and various sub-networks, and this allows us to explain the basis for key experimental findings, and make predictions for experiments. We also study how structural and functional features differ between detailed anatomical connectomes and those generated by our new, simpler, model (meta-model).

Data grid is emerging as the main part of the infrastructure for large-scale data intensive applications such as high energy physics and bioinformatics. The deployment of such infrastructures has allowed users of a grid site to gain access to a large amount of distributed data. Data replication is a key issue in a data grid and could be applied intelligently because it reduces data access time and bandwidth consumption for each grid site. In this paper, we introduce a new dynamic data replication algorithm named Popular Groups of Files Replication (PGFR). Our proposed algorithm is based on an assumption: users in a Virtual Organization have similar interests in groups of files. Based on this assumption, and file access history, PGFR builds a connectivity graph to recognize a group of dependent files in each grid site and replicates the most Popular Groups of Files to each grid site, thus increasing the local availability. We used OptorSim simulator to evaluate the efficiency of PGFR algorithm. The simulation results show that PGFR achieves better performance compared to the existing algorithm; PGFR minimized the mean job execution time, bandwidth consumption, and avoiding unnecessary replication. [ABSTRACT FROM AUTHOR]

We present a graph-theoretical interpretation of the recently developed interface theory of single zigzag chains N(n) in form of connectivity graphs. A remarkable property of the connectivity graphs is the possibility of constructing the full set of Clar covers of N(n) as the complete set of walks on these graphs. Connectivity graphs can be constructed in a direct form, in which the number of vertices is growing linearly with the length n of N(n), and in a reduced form, in which the number of vertices is independent of the actual length of the chain. The presented results can be immediately used for the determination of the Zhang-Zhang (ZZ) polynomials of N(n) in an easy and natural manner. Two techniques for computing the ZZ polynomial are proposed, one based on direct recursive computations and the other based on a general solution to a set of recurrence relations. Generalization of the interface theory to arbitrary benzenoid structures, the construction of associated connectivity graphs, and techniques for the computation of the associated ZZ polynomials will be presented in the near future. [ABSTRACT FROM AUTHOR]

In recent years data grids have been deployed and grown in many scientific experiments and data centers. The deployment of such environments has allowed grid users to gain access to a large number of distributed data. Data replication is a key issue in a data grid and should be applied intelligently because it reduces data access time and bandwidth consumption for each grid site. Therefore this area will be very challenging as well as providing much scope for improvement. In this paper, we introduce a new dynamic data replication algorithm named Popular File Group Replication, PFGR which is based on three assumptions: first, users in a grid site (Virtual Organization) have similar interests in files and second, they have the temporal locality of file accesses and third, all files are read-only. Based on file access history and first assumption, PFGR builds a connectivity graph for a group of dependent files in each grid site and replicates the most popular group files to the requester grid site. After that, when a user of that grid site needs some files, they are available locally. The simulation results show that our algorithm increases performance by minimizing the mean job execution time and bandwidth consumption and avoids unnecessary replication. [ABSTRACT FROM AUTHOR]

In order to systematically analyze Internet traffic features, this paper researched the taxonomy of traffic features based on the objects used for building traffic features,and overviewed the related traffic features in each category. It further analyzed the stability of traff ic features, the impact of packet sampling, network environment and obfuscating on traffic features. And then it compared the different kinds of traffic features from classification accuracy .stability, timeliness and granularity. Finally, this paper concluded future works about traffic features. [ABSTRACT FROM AUTHOR]

We consider the static and dynamic characteristics of interatomic bonding in the region of nonvalent interactions of a nitro group in the crystal of complex [Fe(NO)(SCHNO)]. Based on results obtained by modeling vibrations within the framework of the density functional theory and those of multitemperature X-ray diffraction studies, a purely vibrational nature of the abnormally large atomic displacement ellipsoid of one of the O atoms of the nitro group was revealed and a model for the influence of peculiar features of intermolecular bonding on the observed dynamics was suggested. Using topological analysis of the experimental electron density function, we studied the nature of nonvalent intermolecular interactions of the nitro group and evaluated their strength and directionality in the equilibrium state. The dependence of the 'pseudodegeneracy' region of atom-atom interaction on the nature of the interaction revealed and a method for determining the vibrational smearing of interactions was suggested, which allows one to analyze the stability of the connectivity graph of the crystal. [ABSTRACT FROM AUTHOR]

Globalization, densification, and the urban growth require the establishment of an interdisciplinary set of tools, which will allow the analysis of the morphological, spatial, social and functional qualities of the city. Space Syntax in the urban design is applied in the modelling of the human behaviour by the examination of the spatial configuration of the urban systems. Analysis of the spatial integration, connectivity and visual exposure of open spaces and paths in combination with the land use patterns indicates the areas, which facilitate the social and commercial activities. This approach is implemented on the four residential complexes of the city of Tirana. Results show the correlation between the type and location of the activities and the spatial and visual integration. The applied methodology is suitable for the preliminary comprehension of the social dimension of the urban projects at the design stage. The insights from the study are appropriate to be used as the urban planning policies in the developing countries of the Global South. • The study is focused on the exploration of socio-spatial parameters of four neighbourhoods using the Space Syntax analysis. • Integration and visual exposure analysis indicates the areas, which encourage the social and commercial activities. • Space hierarchy, intelligible street network and well-integrated large open space facilitate the liveable built environment. • Physical, social and syntactic assessment of the residential development should be prioritised by the urban policies. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Signal Processing is the property of Journal of Signal Processing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The main aim of the detailed facility layout is to calculate the obstacle-avoiding Manhattan shortest path (OAMSP) between facilities. We propose a connectivity graph generation approach for OAMSP calculation. The proposed approach makes full use of the characteristics of Manhattan distance, which are different from Euclidean distance. The proposed connectivity graph contains O(N log N) vertices and edges, where N is the total number of all facilities vertices. We give two examples to compare the proposed approach and two classical graph theoretic approaches. The results showed that the proposed connectivity graph possessed less vertices and edges, and the generation time of the proposed approach is also shorter than other two methods. Thus, the proposed approach can shorten the time of shortest distance calculation in detailed layout. Furthermore, the proposed graph can be valuable reference to the transport routing planning. [Copyright &y& Elsevier]

Abstract: Several protocols have been proposed to date to defend against wormhole attacks in wireless networks by adopting synchronized clocks, positioning devices, or directional antennas. These requirements and assumptions limit their applicability especially in the case of mobile networks where the degree of association and de-association between the nodes is relatively high. In this work, we present a novel lightweight countermeasure for the wormhole attack, called LDAC (Localized-Decentralized Algorithm for Countering wormholes). It is completely localized and works by looking for simple evidence that no attack is taking place, using only connectivity information, as implied by the underlying communication graph. LDAC is not confined to static networks but extends naturally to dynamic and even mobile ones. Rigorous arguments that prove the correctness of the algorithm are coupled with detailed performance evaluation along with an implementation on real sensor devices that demonstrates its efficiency in terms of memory requirements and processing overhead. [Copyright &y& Elsevier]